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A061431
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a(n) = LCM of the n consecutive numbers n(n-1)/2 + 1, ..., n(n+1)/2.
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8
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1, 6, 60, 2520, 60060, 1627920, 124324200, 1694579040, 446626220040, 73706596563600, 177223661334720, 171986625946535400, 3290057629552053360, 551042196782556679200, 71028805196838414285360, 5709613258492889617872000, 20986612729658105596044778800
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OFFSET
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1,2
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LINKS
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EXAMPLE
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a(1) = 1, a(2) = lcm(2,3) = 6, a(3) = lcm(4,5,6) = 60, etc.
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MATHEMATICA
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LCM@@Range[#[[1]]+1, #[[2]]]&/@Partition[Accumulate[Range[0, 20]], 2, 1] (* Harvey P. Dale, Jul 30 2016 *)
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PROG
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(Magma) [Lcm([n*(n-1)/2 + 1.. n*(n+1)/2]): n in [1..30]]; // Vincenzo Librandi, Mar 18 2018
(PARI) a(n) = lcm([n*(n-1)/2 + 1..n*(n+1)/2]); \\ Michel Marcus, Mar 18 2018
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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